Autonomic nervous system: Fight, Flight and Freeze

Anxiety is related to our survival instinct, the “fight or flight” response is a series of biochemical changes that saves our lives in times of danger, whether we bump into a tiger or meet someone dangerous. However, living in present day Dublin, our stress response is alerted when we don’t need it. So when we don’t run or fight, we don’t burn off the effects of adrenaline in three minutes, which is what is needed.

Any problem real or imagined, can cause the cerebral cortex, (thinking part) to send an alarm to hypothalamus (the main switch for the stress response) located in the limbic system. The hypothalamus stimulates the sympathetic nervous system to make a series of changes in the body: Increased heart rate, breathing rate, muscle tension, metabolism and blood pressure increases. Our hands and feet become cold as blood is directed from the extremities and digestive system into the larger muscles that can help us to fight or run.

The limbic system of the brain responds to extreme stress/trauma/threat and release hormones that tell the body to prepare for defensive action. Hence, activating the sympathetic nervous system “fight or flight” response. Some people experience butterflies in our stomach, the diaphragm and the anus can lock. The pupils dilate to sharpen vision and our hearing becomes acute. This means we are hyperaroused.

Therefore, while the stress or “fight or flight” response is vital in true emergencies, it wears our body down. With the constant activation of the adrenal glands they begin to secrete cortisol into the system, this can seriously damage every healthy functioning system in our body.

Chronic stress unchecked can also lead to lots of complications: cardiac problems, heart attacks, infertility, insomnia, high blood pressure, migraines, ulcers or irritable bowel syndrome. Usually there are lots of symptoms along the way. Sometimes with sudden cardiac death your first symptom could be your last.